Improved support for dualscreen - different size monitors

[Vadi]

Hi,

It'd be nice if Spring could be configured to work on dualscreen where the monitor widths are different - it right now assumes they are equal and places the vertical division right in the middle. This poses a problem where the monitor widths are different, because a part of the game will be overflowing on another monitor.

The last discussion on dualscreen was here: http://springrts.com/phpbb/viewtopic.ph ... dualscreen but I'm not sure what came out of it.